The grace of Christ does not mean that we enjoy the benefits of being perfect through our covenant after baptism. Our covenant does not work by taking our goodness and combining it with Christ’s perfection yielding a total of 100% perfection on the basis that Christ’s goodness always compensates for our failures. That is simply not how the covenant works and we should know that from our own experience.
If that was how our covenant worked, if that was the means by which it becomes possible for man to enter to dwell with Heavenly Father, then we should have the same experience now dwelling with the God the Holy Ghost. He would be with us all the time. Instead, as we know, when our behavior is less than it should be, the Holy Ghost leaves us. The false protestant atonement doctrines proselyted by some popular Mormon authors would mean that our imperfections are combined by covenant with Christ’s perfections, so that we should always enjoy 100% perfection. By that formula, the Holy Ghost would never depart from us as long as we didn’t actually do something so serious as to invalidate our covenants. But in reality, we find that the better we live, the more closely we have the Holy Ghost, and when we do wrong we drive him away.
Our own experiences with God the Holy Ghost do not match the protestant description of the grace of Christ. And that is because it is a bogus description.
Let us admit the realities of our own experiences learning to dwell with God the Holy Ghost in preparation for dwelling with the Father and the Son. The atonement does not make it so that we will enjoy the benefits of perfection until we actually become perfect. Christ’s interceding grace is real, but He grants forgiveness to us only on condition of repentance. We are not cleansed of misbehaviors until we change and stop doing them.